0.3.0: converge relibc to upstream 0.6.0 + Red Bear patches

tests/waitpid.c

@@ -1,21 +1,38 @@
+#include <assert.h>
 #include <sys/wait.h>
 #include <unistd.h>
 #include <stdlib.h>
 
 #include "test_helpers.h"
 
-int main(void) {
+void for_code(int code) {
     pid_t pid = fork();
     ERROR_IF(fork, pid, == -1);
 
+    // Testing successful exit
     if (pid == 0) {
         // child
-        sleep(1);
-        exit(EXIT_SUCCESS);
-    } else {
-        // parent
-        int stat_loc;
-        pid_t wid = waitpid(pid, &stat_loc, 0);
-        ERROR_IF(waitpid, wid, == -1);
+        usleep(100000);
+        _Exit(code);
     }
+    printf("Testing waitpid of child %d for code %d\n", pid, code);
+    // parent
+    int status;
+    pid_t wid = waitpid(pid, &status, 0);
+    ERROR_IF(waitpid, wid, == -1);
+
+    assert(WIFEXITED(status));
+    assert(WEXITSTATUS(status) == code);
+
+    puts("Success");
+}
+
+int main(void) {
+    for_code(EXIT_SUCCESS);
+    for_code(EXIT_FAILURE);
+    for_code(42);
+    for_code(255);
+    // TODO: Also add coverage for e.g. WIFSTOPPED, WSTOPSIG, WTERMSIG, etc
+
+    return EXIT_SUCCESS;
 }